Science for Saving Species Research findings factsheet Project 2.1 Butterflies on the brink: identifying the Australian butterflies most at risk of extinction In brief Background Terrestrial invertebrates and their Invertebrates are declining globally in high (greater than 30%) chance of habitats are increasingly threatened both diversity and abundance, with extinction. We also identified key by human disturbances, particularly potentially serious consequences threatening processes affecting habitat loss and fragmentation, for ecosystem functioning. Many these species (chiefly inappropriate invasive species, inappropriate fire Australian butterflies are imperilled fire regimes, habitat loss and regimes and climate change. or declining but few are listed fragmentation, invasive species and Continuing declines and extinctions for protection by legislation. climate change), and the research in native terrestrial invertebrate We identified the 26 Australian and management actions needed communities are likely to negatively butterflies at most immediate risk to save them. Mapping of the 26 affect ecosystem functioning. This is of extinction within a 20-year time butterflies’ distributions revealed that because invertebrates play a central frame. We found that one butterfly most are now found only in a single role in many ecological processes, is facing a greater than 90% chance state or territory and many occupy including pollination, herbivory, the of extinction in the next 20 years narrow ranges. Increased resourcing consumption of dead plant and (and may already be extinct), and and management intervention is animal matter, and nutrient cycling, four species have a moderate to required to avert future extinctions. as well as providing a good source of food for other animals. There is urgent need to explore the causes of these declines, and the implications for ecosystems and ecosystem services. We must also put appropriate management actions in place to halt and reverse declines in the species at greatest risk of extinction. Invertebrate conservation and management has many challenges. Invertebrates are generally poorly known and under-studied, and much of their vast biodiversity remains undescribed. Resources are also limited, both in terms of scientific expertise and funds, making it difficult to assess and hence Bulloak jewel (Hypochrysops piceatus). address their conservation needs. Image: Michael Braby Biodiversity and Conservation Science Ento Search LEFT: Larva of the Australian fritillary (Argynnis hyperbius inconstans); its host plant is the native violet (Viola betonicifolia). Image: Garry Sankowsky Background (continued) Although there have been some recent advancements in conservation assessments for butterflies in Australia, these have typically not translated into additions to statutory lists. Just 10 butterfly species are listed for protection under the Australian Government’s EBPC Act. The Australian Government has committed to averting extinctions, and this first requires identification of the species at most immediate The Australian fritillary (Argynnis hyperbius inconstans) on risk. We worked with experts to native violet. Image: Garry Sankowski identify highly imperilled Australian butterfly species and subspecies What we did that are threatened with extinction in the near future. The project consisted primarily of Distributions – We mapped desktop research and structured the distribution of the most The experts included NESP interviews with experts. imperilled butterflies using Threatened Species Recovery Hub distribution data compiled from Identifying at risk species – researchers; amateur entomologists The Complete Field Guide to We produced a preliminary list (who carry much of the natural Butterflies of Australia. See Figure 1. history knowledge of butterflies in of Australian butterflies at high Australia); and butterfly biologists risk of extinction based on all Threats and management – from academic institutions, state available published and unpublished We identified key threats to or federal government agencies information; this included each species from the published and environmental NGOs. They information provided by butterfly literature, conservation listing included representatives from experts, including at a workshop advices, the Action Plan for every Australian state or territory. in 2019. From this we finalised Australian Butterflies, and from a list of 26 species most likely unpublished information from and Research aims to be lost to extinction within observations by species experts. 20 years. See Table 1. We classified the threats using We aimed to: the IUCN Threats Classification Extinction probabilities – Scheme. We used this information 1. identify the Australian butterflies We used structured expert to determine the number and at most immediate risk of elicitation to obtain estimates of proportion of species affected extinction in the next 20 years; extinction probability in the next by the various threat types. 2. estimate their probability of 20 years. Our approach involved extinction (in the wild) by 2040; giving participants relevant We identified relevant research information on ecology, threats and management actions for 3. map their distribution to identify and trends, then asking them to reducing risks of extinction using regions for priority research estimate probability of extinction published and unpublished sources. and management; and over the 20-year time frame of We categorised these actions using 4. identify their key threats, interest. Assessments assumed the IUCN Research Needed to inform key research and current management would and Conservation Actions management objectives continue, with no new Classification Schemes. for averting future butterfly actions implemented. extinctions. Rank Scientific name Common names EX Lower Upper Conservation status in State/ EPBC 95% CI 95% CI Territory of occurence Status 1 Argynnis hyperbius inconstans Australian fritillary, laced fritillary 0.94 0.89 0.97 QLD (EN),NSW (-) CR 2 Jalmenus eubulus Pale imperial hairstreak 0.42 0.28 0.58 QLD (VU), NSW (CR) - 3 Hypochrysops piceatus Bulloak jewel 0.37 0.24 0.53 QLD (EN) - 4 Oreisplanus munionga larana Marrawah skipper, alpine sedge-skipper 0.33 0.2 0.49 TAS (EN) VU 5 Jalmenus aridus Inland hairstreak 0.3 0.15 0.5 WA (P1) - 6 Ogyris sp. aff. aenone Sapphire azure (southern population) 0.28 0.16 0.44 QLD (-) - 7 Ogyris subterrestris subterrestris Arid bronze azure 0.28 0.16 0.44 VIC (Thr), SA (-) - 8 Croitana arenaria arenaria Inland grass-skipper 0.22 0.12 0.36 NT (-) - 9 Heteronympha banksii nevina Banks’ brown 0.19 0.1 0.32 VIC (-) - 10 Heteronympha cordace wilsoni Bright-eyed brown 0.18 0.1 0.3 VIC (Thr), SA (-) - 11 Ogyris subterrestris petrina Arid bronze azure 0.15 0.08 0.26 WA (CR) CR 12 Candalides noelkeri Golden-rayed blue 0.13 0.07 0.23 VIC (Thr) - 13 Antipodia chaostola leucophaea Tas. chaostola skipper, heath sand-skipper 0.11 0.06 0.19 TAS (EN) EN 14 Acrodipsas illidgei Mangrove ant-blue, Illidge’s ant blue 0.1 0.05 0.17 QLD (VU), NSW (-) - 15 Oreixenica ptunarra Ptunarra xenica, ptunarra brown 0.09 0.05 0.17 TAS (VU) EN 16 Ogyris otanes sublustris Western dark azure 0.09 0.05 0.17 WA (-) - 17 Ogyris iphis doddi Dodd’s azure, orange-tipped azure 0.07 0.03 0.14 NT (EN) - 18 Hesperilla flavescens flavescens Yellow sedge-skipper 0.07 0.03 0.14 VIC (Thr) - 19 Exometoeca nycteris Western flat 0.07 0.03 0.14 WA (-) - 20 Oreixenica latialis theddora Small alpine xenica 0.06 0.03 0.12 VIC (Thr) - 21 Ogyris halmaturia Eastern bronze azure 0.06 0.03 0.11 VIC (Thr), SA (-) - 22 Ogyris otanes otanes Small bronze azure 0.06 0.03 0.11 NSW (-), VIC (-), SA (-) - 23 Ocybadistes knightorum Black grass-dart 0.05 0.03 0.1 NSW (EN) - 24 Telicota eurychlora Southern sedge-darter 0.03 0.01 0.05 QLD (-), NSW (-), VIC (Thr) - 25 Paralucia spinifera Purple copper, Bathurst copper 0.03 0.01 0.05 NSW (EN) VU 26 Hypochrysops apollo apollo Apollo jewel 0.02 0.01 0.04 QLD (VU) - Table 1. The scientific and common names, likelihoods of extinction based on structured expert elicitation with lower/upper 95% confidence intervals, and listed conservation status in state/territory of occurrence and under EPBC Act for the 26 most imperilled Australian butterflies. (- denotes Not Listed). Key findings Of the 26 butterflies included in with no confirmed specimen but some are believed to be locally our assessment, only six were listed records since 2001. Another four extinct. For example, the small as threatened under Australian butterflies had a moderate to high bronze azure (Ogyris otanes otanes) federal legislation (the EPBC Act) probability of extinction (30–50%). is most likely locally extinct in New South Wales and possibly Victoria, as of February 2020, with a further We estimated that five butterflies with surviving populations confirmed two nominated. A larger number could be lost to extinction by 2040 only in South Australia, while the (20) were recognised as threatened unless management improves, and under the relevant legislation there was a high level of agreement eastern bronze azure (Ogyris for one or more of the states or about this among experts. halmaturia) is almost certainly locally territories in which they are extinct from its formerly wide range All 26 species of Australian known to occur. in western Victoria, and now persists butterfly are found nowhere else precariously at only two or three The Australian fritillary (Argynnis but Australia, and 18 are found locations in South